Friday, 18 November 2011

Meteorites and meteowrongs

Most days, a meteorite will fall to Earth somewhere. Almost all of them are stone, with only a small percentage iron-nickel or stony-iron. It's hard to recognise a stony meteorite - with an iron one you can feel the unusual weight, cut it to see the metallic sheen inside, etch it for crystal pattern and so on. With a stony one, it usually just looks like a slightly shiny stone. And there are plenty of them lying around. I'm sure you've noticed. So how do you find a meteorite?

Short of one smashing a hole in your house or flattening your car, chances are you're not likely to come across one, but it's not impossible. It was once thought the chances of finding a meteorite were too low to bother, but one man made it his life's work to change that perception. In 1923 Harvey Nininger, a teacher, saw a fireball and became fascinated with meteorites. Eventually he quit his job to focus on hunting them, and he was offered space in Denver Museum, with his collection on display. He worked out a system. 'Go out and educate the people; tell the people what they're like, offer a bonus if they find any. And in a country where the land is farmed, they will turn these things up. And that's the way I made the collection.' In 1946,  he founded the American Meteorite Museum near Winslow, Arizona, close to Meteor Crater. By this time he'd built up an enormous collection of material, and he began to push for the study of meteorites to be taken more seriously. The museum moved to Sedona after a new highway was built, and when business began to fall away, Nininger sold his collection to the British Museum and the Center for Meteorite Studies at Arizona State University. He was now in a position to spend more time hunting, so went back to his hobby while writing books and giving lectures on the subject. Science owes this man a great deal.

I frequently get people bringing me their 'meteorite' finds. So far there hasn't been a meteorite among them. Pyrite nodules quite often. Industrial slag. A piece of pottery. Some galena and a lot of... well... pebbles. But, you never know. There was a nice story earlier this month about a farmer who in 2006 had found a big lump of pallasite, spectacularly speckled with olivine. He cut a bit off, realised he had something special, and it ended up being recently designated a new find and given its own name - Conception Junction, after the town in Missouri where it was found. So there can be a happy ending.

1 comment:

John Tossot said...

Is that stone kind of sedimentary stone? it is looks like stone at fossils for kids where it labeled as sedimentary stone